Pond Boss
Posted By: Todd3138 Floating Island/Wetland - 02/02/13 11:47 PM
So I've been all over the place on my thoughts about how to best construct a floating island/wetland for one of my ponds. I have to admit that the product put out by Bruce Kania at Floating Islands International looks to be simply fantastic. Of course, the pricing I am finding is also simply fantastic, but not in a favorable way for a small farm pond.

I have beaten my head against the proverbial wall trying to locate a material similar to what FII uses for its island products, all to no avail. I have found tons of other things that might work, though, and wanted to bounce the idea here. I'm also awaiting some info from forum member Peepaw, proprietor of Fishiding, as to a source for the material.

In the meantime, I was at Joann Fabric with my wife today. While meandering through the store, trying to find something redeeming about the experience aside from spending time with her, I came across furniture foam and the wheels starting turning. My big question is whether or not the wheels are turning in such a way that they're about to fall off!

This foam, which I've found through other sources online, comes in thicknesses of 1" to 5" and is advertised as a high density foam. Here is a link to one site that sells it in lengths longer than the fabric store had in stock.

My thinking was to get perhaps four sheets of this stuff in the 108" length at 30" wide (it also comes in 24" wide pieces) so I would have a 9x10 platform for a floating island. Then, to somewhat mimic the concept behind FII's products, I would add several inches of poly batting to the bottom for a more effective growth media to get the periphyton action started. I was thinking something like this might be good material.

I would need to find a way to bond the batting to the foam and would likely also consider building a frame of pvc with a couple of cross members for overall added buoyancy additional support. I suspect the batting would become extremely heavy once waterlogged and, in addition to the weight of the soaked foam and the topsoil on the island, the thing would be a real bear in terms of weight.

Anyway, my question is: what do you guys think? And no, I'm not asking what you think about my spending time in a fabric store and perusing online craft/sewing websites. I already feel bad enough about that aspect of this project so cut me some slack! One good point today was when I told the lady at the fabric store what I was thinking about, she commented that she had never had anyone ask about the foam for that sort of use, so I did feel a little bit redeemed!

Anyway, share your input with me on how this might come together. I think if these materials were suitable, I could do the whole thing for under $600 depending on how thick I would want to go on the foam - that is a huge variable right there. In any event, even with the thickest foam, I think it would be easy to stay under $1000.

Ideas?
Posted By: Instar Re: Floating Island/Wetland - 02/02/13 11:59 PM
Sounds like a good start. I would forget about the topsoil....too much weight and not really necessary....and use a different substrate to provide anchorage for the plants. They will derive nutrients from the water. What immediately comes to mind is light weight Coir (coconut fiber). Not sure of a bulk source, but could probably find it easy enough with Google.
Posted By: esshup Re: Floating Island/Wetland - 02/03/13 12:12 AM
Todd:

I'd give some thoughts to closed cell foam, something like the very stiff kneeling pads or exercise mats are made from. There is a local place where I can buy 2"x24"x96" closed cell foam mats that are seconds pretty durn cheap. I placed some in the pond in 18" squares for FHM spawning areas, and after 3 years in the sun they still are in fine shape with no UV protection. They are black in color.

The open cell foam will absorb water and might sink. Look for UV protected stuff too.
Posted By: fish n chips Re: Floating Island/Wetland - 02/03/13 12:23 AM
I don't know if this will help, but I think it was John Monroe (sp?) that had a pretty extensive thread on his experience building a floating island. It was about a year ago?

Edit: here is the thread I was thinking about http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=298434&page=6 . Apparantly is was started by AP and then Monroe tried his version starting around page 6.
Posted By: Todd3138 Re: Floating Island/Wetland - 02/03/13 12:29 AM
Originally Posted By: Instar
Sounds like a good start. I would forget about the topsoil....too much weight and not really necessary....and use a different substrate to provide anchorage for the plants. They will derive nutrients from the water. What immediately comes to mind is light weight Coir (coconut fiber). Not sure of a bulk source, but could probably find it easy enough with Google.


Good thought, Instar. Might even be worth looking at peat moss or something similar. I'll look up info on coir, too. Heck, wood chips might be good also, or even sawdust.
Posted By: Todd3138 Re: Floating Island/Wetland - 02/03/13 12:32 AM
Scott, where would you use that foam in this mix? To gain some of the colonizing benefit of the periphyton, it seems like you really want something like the poly batting to offer tons of growing space in a small package - the porous nature of the batting is what I understand provides the massive amount of surface area.

As far as water logging and perhaps sinking, that's why I am thinking a pvc frame for buoyancy. And with respect to UV damage, I would think that a total cover with something like dirt, saw dust, wood chips, coir, etc. and plant life would provide all the protection needed to avoid any UV breakdown. Am I missing something along those lines in your opinion?
Posted By: Todd3138 Re: Floating Island/Wetland - 02/03/13 12:36 AM
Originally Posted By: fish n chips
I don't know if this will help, but I think it was John Monroe (sp?) that had a pretty extensive thread on his experience building a floating island. It was about a year ago?

Edit: here is the thread I was thinking about http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=298434&page=6 . Apparantly is was started by AP and then Monroe tried his version starting around page 6.


Thanks, fish n chips. I actually followed John's thread pretty closely and he did a beautiful job. I am shooting for a different application, though, as this stage. I had originally considered that sort of project when John started his, but have since decided I really like the food chain/nutrient cycle impact that this sort of floating island has, again, a la Floating Islands International. I have a very nutrient heavy pond and, while I have eliminated some of the biggest causes of nutrient overloading, I still need to go after them and feel this is another good step. The other sort of floating island does not appear to have the same level of impact, although it is certainly a positive for a pond.
Posted By: fishm_n Re: Floating Island/Wetland - 02/03/13 01:01 AM
Have you looked at miners moss. I think this stuff would work great for letting your plants get to water.

http://www.google.com/search?q=miners+mo...920&bih=989

Kinda spendy though, but should last
Posted By: Todd3138 Re: Floating Island/Wetland - 02/03/13 01:14 AM
Interesting product.
Posted By: esshup Re: Floating Island/Wetland - 02/03/13 02:39 AM
Todd:

I missed the part about the PVC. Sorry. I was thinking of the closed cell foam for the flotation portion of the island. It's easy to cut slits in it with a sharp knife (even an electric fillet knife works well) and you can push the hanging material thru from the bottom and tie it off on the top size.

Have you looked at some of the craft stores for x-mas garland? Tie on top, use a small weight on the other end to make sure it hangs straight down. They use something like that to make cover areas for ice fishing that are removable. Drill a hole, slip this thing down the hole, the arms unfold and the garland sinks downward. Drill more holes around the perimeter of the cover and target the fish that come to check things out.

They also have plastic "spanish moss" that is also used for decorations, but that might be too tight.
Posted By: Todd3138 Re: Floating Island/Wetland - 02/03/13 03:51 AM
No worries, Scott.

My plan/concept is to make numerous holes to allow plants to get established and get their roots to the water, but obviously those roots will die off some during the winter. It might make sense to have some permanent fixtures hanging down as a supplement for the non-growth season. I like the idea of the garland - it'll probably last a long time.

Does anyone have any thoughts on the thickness of the top foam layer? I don't want to go too overboard but also want to ensure there's enough to do the job effectively. The 5" foam seems pretty darn thick and buoyant, but it will also get awfully heavy as it saturates. I wonder if there is a break even point with the thickness.
Posted By: Robert-NJ Re: Floating Island/Wetland - 02/03/13 04:18 AM
Todd how big of a island are you looking to make?I've had some good ideas floating around since reading AP's old thread that I have played with a little.

Also I think instar is on the right track as far as media goes,there is also rockwool and a few other hydroponic items that are light and suitable for island use.
Posted By: Todd3138 Re: Floating Island/Wetland - 02/03/13 06:39 PM
Thanks, Robert. I am considering something in the range of 10x10 initially. Depending on how it goes, I might later add some others, but for starters, that 10x10 is the general target size.
Posted By: adirondack pond Re: Floating Island/Wetland - 02/03/13 07:22 PM
Todd if your looking to build an island with plenty of plant roots extending into the water, using plastic fence mesh worked well for me, I covered it with newspaper then put a mixture of peatmoss and potting soil on it, the media on it has filled with roots and held up well after almost 4 years.
The flexible plastic pipe filled with foam and swim noodles has provided enough floatation, but if you were to build a large island 4 inch corrigated pipe could be used to shape the island then drill holes in it to fill with great stuff expanding foam, this would probably give you enough floatation.
After zip tying the plastic mess across it add small pvc pipe bracing to help hold it's shape.
The christmas garland I used was purchased at the Dollar Tree store, the stem is metal coated in plastic and the pine needles are also plastic, it also has held up well and there is no need to weight it as the metal makes it sink.

Just some thoughts on contruction, there's plenty of ways to experiment, good luck.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=312455&page=3
Posted By: Todd3138 Re: Floating Island/Wetland - 02/03/13 07:43 PM
Thanks, buddy. It was actually your island that really got me thinking about making one for this pond and then the whole FII deal really got me thinking about how much more it could potentially be.

By the way, how is your island holding up? Last I recall reading about it, it was still doing well though showing some signs of the support structure aging.
Posted By: adirondack pond Re: Floating Island/Wetland - 02/03/13 07:51 PM
Originally Posted By: Todd3138
By the way, how is your island holding up? Last I recall reading about it, it was still doing well though showing some signs of the support structure aging.


It was ok in November till the ice and snow covered it, won't find out till April, the flexability of the materials I used probably help it survive the pressure of ice and snow.
Posted By: Todd3138 Re: Floating Island/Wetland - 02/03/13 08:01 PM
Be sure to share some pics once it emerges!
Posted By: Bill Cody Re: Floating Island/Wetland - 02/04/13 02:13 AM
I like adirondack pond's idea of using 4" dia corrigated black pipe filled with expanding foam as a floation collar. The plastic fencing will work as a bottom mesh. Use the PVC pipe as inside framework to keep the shape and add a little floatation if ends are capped. A thin layer of peat moss should work as a planting medium. Once the plant roots are well established the root mass will unite the whole structure and should add floatation similar to a floating bog.
http://www.youtube.com/watch?v=8PFIHgcPgNs
http://www.paynesvillearea.com/news/headlinesarticles/archives/061803/0618bogs.html

Sample Floating Islands
http://www.cherokeemarsh.org/files/Apr_18_2012_Friends_Cherokee_handout.pdf
Posted By: John Monroe Re: Floating Island/Wetland - 02/04/13 11:01 AM
Todd before you spend money making a island raft system thinking the plant roots will just angle in the water and grow OK, read the link below. It sounds so simple but the roots become black and the plants yellow and eventually die because the unfiltered water particles collect on the roots. Before I made my island I ran a test of a floating plant in my pond and it turned yellow and died. At the same time another pond boss member said he had the same problem. When I planted my island using dirt as a filter which allowed healthy rigors plants I also put one plant in the island with it’s roots dangling in the pond. It stopped growing, turned yellow and died. I pulled it and the roots were black. As far as I can tell plants do just fine in any filtered water, natural or mechanical. In my foam island the ropes draw water into the soil but actually the island is heavy enough that water freely flows into the dirt because the island is low enough for water to flow in without the ropes. Ropes are probably not even necessary and just holes would be OK.
The link below really proves the point.

http://blog.aquaponicssystems.com/2009/07/aquaponics-in-fishponds-on-floating.html

Here are dozens if not hundreds of aquaponic raft systems.
https://www.google.com/search?q=aquaponi...800&bih=434
Posted By: Bill Cody Re: Floating Island/Wetland - 02/04/13 04:48 PM
The specie of plant may play a role as to how well it will grow in water without some type of soil substrate. Some plants are much more tolerant of hydroponic live than others. Homework will be necessary for success.
Posted By: adirondack pond Re: Floating Island/Wetland - 02/04/13 08:05 PM
I agree with John that some plants won't do well when their roots are just in water, but as Bill said there are certain species that will thrive in a hydroponic enviroment.
The other factor in selecting plants that will survive on your island is your climate, all the different water loving species I planted the first year grew well but only the swamp grass, water Canna, and Iris survived the winter with the water Canna not surviving the second winter.
The Cattail planted itself and survives along with the Iris and swamp grass. I'm sure there are many more plants that will survive such as the pickerel weed which I have on my natural islands but never planted them on the artificial island.
Posted By: Bill Cody Re: Floating Island/Wetland - 02/04/13 10:05 PM
Adirondackp - do the roots hang very far into the water below your island? If you lift one corner of the island what does it look like underneath?.
Posted By: adirondack pond Re: Floating Island/Wetland - 02/05/13 01:26 AM
Bill I'll have to check that out this spring, my son has a small camera that can take photo's in shallow water, I'm curious myself.
Posted By: Bill Cody Re: Floating Island/Wetland - 02/05/13 01:59 AM
It will be very interesting to get an underwater view of the bottom of your floating island. Picture taken underwater will show the natural dangling of the roots below the island. Just a picture of a corner lifted would also give a pretty good idea of the texture and structure underneath the island. I bet an island similar to yours is pretty heavy.
Posted By: John Monroe Re: Floating Island/Wetland - 02/05/13 09:26 AM
Adirondack looking back at your island pictures I see you used some dirt and peat although not real thick but which would give some filtering to your plants. Even with water loving plants my guess is most of your roots are in the growing medium and very little dangling in the water below your island. If you could take two pictures, one in the spring when planted when some nice white roots might be dangling and then another picture in the fall to see if the roots are black or have rotted off. I have often wondered how pure water plants with their roots only in the water have evolved to survive without root rot, like the Water Hyacinth. Perhaps you know Bill? My island has been frozen in ice and buried snow several times this winter and every time it has thawed so far I have a green mustered spinach plant surviving. It must be really tough.


Posted By: adirondack pond Re: Floating Island/Wetland - 02/05/13 02:27 PM
Yeah John I plan on taking photo's now that you guys have gotten me curious.
I think if there's one plant on that island that could grow without soil it would be the Cattail, they could thrive on a bowling ball.
That's another good reason to put in artificial cover like the garland I have on it, I've seen small GSH around the edges and the island is over 8ft. of water where the trout like to be.
Posted By: esshup Re: Floating Island/Wetland - 02/05/13 03:36 PM
Bob Lusk has a floating island at the end of the pier on the pond at LL2. IIRC it's been in the pond for a number of years. I wonder if he knows what the root system under the island looks like?
Posted By: Bill Cody Re: Floating Island/Wetland - 02/05/13 05:11 PM
I do know that aquatic iris survive well growing in 1/2"-3" sized rocks submerged in water. I know they grow bullrush and iris in baskets with just gravel/rocks in water. The rocks I think are just to hold the plant upright and in place. Cattails and numerous other wetland plants tolerant of anoxic soil conditions would also probably grow just water. The neighbor has a greenhouse where he raises hydroponic lettuce and the root mass gets to be 12"-16" long from mature lettuce roots growing in the dark with just water around it.
Posted By: John Monroe Re: Floating Island/Wetland - 02/06/13 09:03 AM
Bill do you know if your neighbor's lettuce is growing in water that has been filtered in his hydroponics set up? Also I have read that a growing medium even like coarse rocks will collect the particles and let them break them down so the nutrients can be used by the roots.

Adirondack I have one of those cheap underwater camera that I was going to use to take pictures last year under my raft of the one plant root, and to see if minnows were feeding off the bottom of the raft, and if fat head minnow were spawning on the underside, but the water quality with the tannin I have didn't seem like a good idea. But the one flowering plant I did have set up with the roots dangling so I could pull the cup out periodically and inspect the roots. That plant at first did grow just like the others and it's long dangling roots were white. Then in a few weeks the growth slowed down and started to die and the roots turned black. Later I inspected the plant and the roots completely rotted off.
Posted By: phytomike Re: Floating Island/Wetland - 05/17/13 09:21 AM
Coir is a good option and it is organic. Paul Kay of Rogue Water came up with something he calls a "botanical burrito". You can roll some inert media like lava rock or expanded clay in a bit of coir (not too dense of coir for this application) and maybe a wee bit of compost (i agree with posters that the nutrients in the water should be sufficient for growth, but a head start wouldn't hurt the plants...still, you don't want to add nutrients to the water if they are a pollutant that you'd like to remove from the water).
Roll about four of these up like large burritos and poke holes in their tops to insert bare-root native sedges, rushes, or whatever wetland plants you like. Then lay about four "burritos" in a standard nursery flat. (Be sure they get saturated when deployed!) Paul floats these in a PVC frame that provides adequate flotation. (He says that it is important to get the dimensions of the frame very exact to hold the flats securely.) Other frame and floatation options could be considered. As an experiment, I successfully grew some plants in a burlap sack filled with nothing but dried blackberry canes and empty water bottles (almost free material) that I floated in a creek.
You might look atnorth fork natives, wetland sod to get an idea about how little substrate wetland plants need to thrive.
I know I haven't added much about building the floating structure (many experiments swirl in my head!) but hopefully these materials and methods help stimulate some ideas...good luck!

Attached picture floating planter, roots, botanical burrito, ecoreactor 025.jpg
Attached picture floating planter, roots, botanical burrito, ecoreactor 026.jpg
Posted By: phytomike Re: Floating Island/Wetland - 05/17/13 09:51 AM
Here's the rice-sack planter I mentioned in my post. It's planted with Carex obnupta and Juncus sp. The tree is an Oregon Ash cutting -- my "tree bobber" experiment. I have a bit of video of some baby fish hanging out by the roots shortly after I set it in the creek; they seem to like it. Also, the plants (Carex glauca) in the other pictures were grown in a water treatment tank, the Eco-Reactor at the Oregon Garden, which is circulated with an "air-lift" system. Try looking up John Todd (toddecological?) to find info on that sort of system.

Attached picture tree bobber and floating planter.jpg
Attached picture tree bobber.jpg
Posted By: adam klaus Re: Floating Island/Wetland - 05/18/13 07:29 PM
Really inspiring thread here. Beautiful stuff AP, and others.

I have wanted to float an island to grow some lettuce during the heat of the summer when it just suffers in the garden. Curious to hear more from Bill about the practicality of that idea.

I have a large coir mat that I convinced the wife to sacrifice for a floating lettuce island. I was thinking to build a floating framework from 1 1/2 inch ABS pipe, lay 1/2 inch plastic mesh over that, layer of newspaper, then the 2" thick coir mat, and finally a little potting soil for the plants to germinate in.
Is there something I am overlooking in this plan?

cheers fellas-
Posted By: Bill Cody Re: Floating Island/Wetland - 05/19/13 03:08 AM
During June July Aug the greenhouse owner uses a special strain of bib lettuce that tolerates higher temperatures in the greenhouse. Water to each row of the lettuce (abt 16 heads) is supplied by a constant flow of water from a small diameter tube. Seed sprouts in a foam block and then each block is inserted into a hole of a 3"-4"wide x 10ft long growing "trays". Water from tybe drains through the tray and exits the end and then is recycled.
Posted By: John Monroe Re: Floating Island/Wetland - 05/19/13 09:18 AM
I still haven't replanted my island yet this spring. Turtles and frogs both share it. The turtles like to lay on the fake foam rocks while the bullfrogs seem to like the moist dirt so I am deciding wether to leave it like it is or to plant something.
Posted By: phytomike Re: Floating Island/Wetland - 05/19/13 09:48 PM
Bill is right that plant selection is important to having a successful floating island. Wetland plants are most suitable for creating extensive root systems in water column because they are built to tolerate low oxygen conditions -- they have aerenchyma (hollow) tissues that allow for gas exchange throughout the plant. Lettuce and other likely food plants aren’t tolerant of saturated conditions like wetland plants are and I think root dieback would be predictable without some method of aeration. System and plant choices are going to be determined by your objectives.

I like John’s foam island and think it looks pretty cool. It looks like he was able to get some petunias to do well in it and it turned into a decent turtle hang-out. That design stays moist by wicking and infiltration of water, but the roots are probably well separated from submergence. It’s a really different approach with different possibilities for plant choice, aesthetics, etc. than a typical floating wetland. Adirondack’s planter probably does have a fair amount of roots under water (haven’t seen pictures) because of plant choice and design differences. If you want to grow lettuce in something like adirondack's planter (I like the plastic fencing idea a lot!), or in what you (adam) described, aeration would probably be a big help.

I think the filtration John refers to above may have more to do with the microbiology that breaks down ammonia than with filtering particulates. I looked at the post he linked to about the lettuce growing experiment and I’m not 100% convinced of the conclusions there. (I don’t know much about aquaponics (yet!) besides the fact that they usually use circulation systems, so I had to research the filtration aspect of it. Here's a decent article that seems to stress importance of “surface area” for microbial communities in aquaponics.)

The explanation of the problem in the lettuce experiment says that the roots weren’t getting enough oxygen because the solids (fish poo) were coating them. Solids probably do play a role in limiting oxygen to the roots, but I’d guess the dead roots in that trial just drowned as much as anything. If the water is too static, it’s not going to be as oxygenated as a re-circulating aquaponic system (RAS) would be. I wonder if aeration would be enough to overcome that root “coating” problem? I’d try experimenting by running a few feet of ¼” soaker hose (or and airstone) under one of those floating trays of lettuce, hook it to an (even dinky aquarium) air pump, and see if the roots and growth come out any different before I’d conclude that filtration is the main/only problem there. I could be wrong, but all the aeroponic, auquaponic, and hydroponic systems for horticultural products I’ve seen use some form of aeration and I think not having it was the biggest limiting factor for that experiment.

In any case, whether you are growing lettuce or wetland plants, floating plants and the associated biofilms on their roots are going to be more successful with aeration. Without it, you’re gonna have to adjust your plans and/or your expectations.
Posted By: John Monroe Re: Floating Island/Wetland - 05/20/13 07:05 AM
Phytomike you have given the best overall explanation of how different kinds of plants grow in water environments that I have seen. Thanks for putting it all together and making sense of it.
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